The present disclosure relates generally to estimating solar power at a sensor location and, more specifically, to real-time estimation of solar irradiation.
Solar irradiation received by a photovoltaic energy conversion system may deviate from theoretical values throughout a day even in the absence of visible clouds or other visible obstructions. For example, particles, humidity, pollutants, etc. may cause diffraction and absorption of solar energy as it travels through the atmosphere. Analysis of field collected data collected shows that the direct irradiation power loss can be as high as 20% of a corresponding theoretical power. Depending on the atmospheric conditions, the percentage loss can be fixed, linear, and/or non-linear with time throughout a clear day. Thus forecast accuracy may be degraded due a variable loss factor at a given solar conversion facility.
Mathematical analysis may be used to provide a compensation factor that may be used to adjust a predicted solar power. For example, a mathematically predicable irradiance value may be scaled by a fixed parameter for a given location based on past measurements. Forecasting methods employing fixed parameters may be simple to implement but may not account for variations in atmospheric conditions throughout a day. Thus, improved prediction tools are desired.